The GMDX Summer VHF Challenge 2025: 6m & 4m CW, Voice and Digital Modes
The GMDX Summer VHF Challenge will take place beginning 00:00 on Monday 12th May until 2359 on Sunday 6th July.
All GMDX members worldwide are welcome to enter.
This is a single event using CW, Voice or Digital Modes on both 4m and 6m bands. Acceptable voice modes are SSB, AM or FM. Entrants are expected not to set up FT8 or Digital modes in automated robot mode. You are trusted to operate your station manually.
The overall winner will have worked the most 4-digit maidenhead locator squares (e.g. IO72) on 4m and 6m to give the highest combined score. In order to have the leading score, it is expected operators would have to make contacts on both 4m and 6m using all modes. Note that DXCC Countries are not counted, only locator squares.
CHANGE FOR 2025: Please note that you can work the same locator on multiple modes on 6m and 4m. Each locator square worked on each mode and band will count towards the total for each band. For example, work a station in IO72 on Voice, CW and Digital on the 4m band. These 3x QSO’s will count towards the 4m locator total. You can also work IO72 again on all modes on 6m band for another 3x additional locator square QSO’s towards the 6m locator total.
A league table will be produced fortnightly. GMDX will provide prizes to each mode leader and the overall leader. The results tables will be based on total of 4-digit maidenhead locators worked on 4m and 6m for each station.
Submit your cumulative totals fortnightly as per table below. We will publish the tables as soon as possible after the cutoff. Final submission during Monday 7th July
Entry submission dates
- 1. 18:00 on Sunday 25th May
- 2. 18:00 on Sunday 8th June
- 3. 18:00 on Sunday 22nd June
- 4. 18:00 on Monday 7th July
Submit your totals using this form https://forms.gle/EKpDBTCt8K4CNEVW8
If you don’t work a band or mode just enter 0.
Please note, operators are requested to send in their updated and current scores fortnightly. Any operator sending in a winning score on the final week with no previous entries will not be included. In the event of 2 or more operators having the same total number of locator squares, the station with the most mode slots will be the winner.
In all disagreements the GMDX judge’s decision will be final.
For the purposes of a Digest article and Website content, please send details and photos of your station, especially antennas and perhaps a note of a memorable contact to mm0gpz@gmail.com
Good Luck and 73
Gordon MM0GPZ
Summer VHF Activity Challenge 2025
Period 1 Results
This year we have tweaked the rules so that a CW, Voice or digital QSO with stations in a single locator square will now count as 3 QSO’s rather than 1 as in previous years. This allows more potential for scoring QSO’s and therefore more activity.
Unfortunately, only 3 reports were received although conditions have been reasonable into EU and many contacts were also made into NA/SA. Hopefully many Ops will post reports at the end of 2nd period on Sunday 8th June.
Here are the results of the GMDX Summer VHF Activity Challenge after the 1st two-week period.
Martin GM8IEM is just in the lead with a grand total of 152 locator squares. GM8IEM’s QSO’s are all digital with 127 on 6m and 25 made on 4m. MM0GOR QSO’s are all on 6m with 16 CW, 4 SSB and 130 digital.
Next submission date/time is 18:00 on Sunday 8th June
Good Luck and 73
Gordon MM0GPZ
Period 2 Results
Six reports were received for period 2, up from three reports in period 1. Conditions have been excellent over the period.
Martin GM8IEM retains the lead with a grand total of 358 locator squares, slightly ahead of Gordon MM0GOR on 341 and new entrant Tom GM4FDM on 177.
Next submission date/time is 18:00 on Sunday 22nd June.
Plenty of time to get active, so let’s get some more reports sent in.
Good Luck
73 Gordon
MM0GPZ
Period 3 Results
11 reports were received for period 3 which is great to see. 13 stations have now entered reports.
Martin GM8IEM just retains the lead with a grand total of 447 locator squares only just ahead of Gordon MM0GOR on 442. GM4FDM maintains 3rd position with 266 locators.
I am especially grateful to Gordon MM0GOR and Martin GM8IEM who have both sent detailed reports of their activities. See below.
I would be delighted for op’s to email me separately if they would like to share details of unusual or memorable QSO’s such as a new DXCC or hard to get locator squares.
Please note that the last date/time a QSO can be logged is 23:59:59 on Sunday 6th July. The final submission date/time is 18:00 on Monday 7th July.
We will be delighted to publish any new logs submitted so please get active and get the logs in.
Good luck.
73 Gordon
MM0GPZ
Activity report from Gordon MM0GOR
Late May and June have been pretty good on Six, with EU sporadic E openings most days and/or evenings.
Some highlights:
22/05 – Late night conditions to South America worked CE, PY, KP4
23/05 – Another late night DX opening to North America Eastern Seaboard and Canada until just after midnight
27/05 – Good DX conditions to South worked D2, PY and S01
28/05 – Late afternoon DX to East worked 9K, UA, 4X, 5B
29/05 – Early afternoon DX to Caribbean KP4, P4, PJ4, PZ5RA (6m ATNO) and V26OC (6m ATNO) worked
31/05 – Evening conditions to South worked EA8, CT3, S01, 9J2FI (6m ATNO)
03/06 – Big afternoon EU opening and worked ZA for 6m ATNO along with FR4OO (6m ATNO) on same beam heading 5-minutes later. This was followed by very late and short opening to NA around 1am
04/06 – Morning DX opening to Middle East worked 4X, 9K, A7, HZ then big EU opening all afternoon, conditions swing to South America for a short while with lots of PY worked and then big NA opening to Eastern states in the evening
14/06 – Opening to NA Eastern states during ARRL June VHF contest
18/06 – Late afternoon DX to Asia worked EY Tajikistan (6m ATNO), UN Kazakhstan, BY and UK decoded but not worked
19/06 – Another Middle East opening worked 4L, A7, A9, TA7 then swing to West in afternoon worked CU8, KP4, TI
20/06 – Worked all 4X evening, along with OD, TA
21/06 – Afternoon DX opening to NA worked pockets of stations in IL, OH, and several in TX. Short opening to PY and 9Y in the evening. Strange pocket opening to Western US around 21:30z worked 1x NM and 5x stations in CO only one after the other, then gone.
Activity report from Martin GM8IEM
All below are FT8 unless otherwise stated, times UTC.
12-31 May: The contest got off to a good start with some lengthy 6m single and double-hop sporadic E openings giving a good baseline of squares. Later in this period there were brief openings into the Middle East.
15 May: Nice opening into PY7 around 2200 UTC with 5 new stations worked, though only 2 grids, HI21 and HI22.
23-May: MUFs increased sufficiently for the 4m band to open into Europe on and off between late morning and mid-afternoon. In the days that followed there were some brief 4m openings.
29-May: 4m was open to Europe during the morning, the best DX being 9H1TX (JM75). Several Italians were worked on their FT8 frequency of 70.190 MHz.
31-May: 6m was open to EA8 during the early evening, and a big surprise was for ZD7BG (IH74) to come up strongly for about 10 minutes on the frequency of an EA8 I’d just worked for an easy QSO.
03-Jun: During the afternoon conditions picked up and there was some excellent Es on 2m (I think), 4m, and 6m. 4m was open into Europe from just before 1600 until I had to go out 40 minutes later. When I returned at 1918 there were still a few 4m stations to be worked before an opening into eastern North America on 6m started which lasted until past 2250. Towards the end of the opening as things slowed down, more Europeans were worked on 4m since the band was still open.
04-Jun: The day started with 6m open to the Middle East, with A71, 5B4, TA and 4X worked, in addition to closer Europeans. 4m was also open to Europe. Unfortunately, we had a scheduled power outage which lasted from 1000-1320 while a local new build had its power connected. Conditions were still good when the power returned, though I had to go out to work at 1600 and didn’t return to the ham shack until 2039 to find a good 6m opening to PY2 and PY5 which led to 6 new stations worked in 3 grids, followed by the best DX of the day, LU1HLH (FF78), worked at 2111. Propagation then moved to Puerto Rico and on to eastern USA and Newfoundland for 5 new locator squares, before I pulled the big switch at 2230. Pleased with a good day’s DXing but still wondering what I might have missed.
5-19 Jun: Uninspiring conditions and it was hard going finding unworked grids. Unfortunately, conditions were very poor during the UKSMG Summer (SSB/CW) Contest on 7/8 June and only two squares were worked in SSB and none in CW. The only bright spots of the period are noted below.
11-Jun-25: HZ1DG (LK18) made a brief appearance on 6m an otherwise quiet band for a new grid.
14-Jun: S01WS (IL47) switched from 6m FT8 to SSB at 1425 and was pounding in for a quick and welcome phone QSO.
20-Jun: Brief 6m opening into Florida from 1300 during which 6 stations were worked in quick succession for a few additional grids. Three 4X stations worked in the 30 minutes from 1850.
21-Jun: Patchy trans-Atlantic conditions, with 3 stations in eastern USA/Canada worked between 1425 and 1503, PY8ABH (GI58) at 1755. The Caribbean provided
two NP3, two 9Y4 and the highlight of the day, J88BTI (FK93) at 2000. Poor conditions for the first day of the RSGB 50MHz Trophy contest during which I’d hoped to pick up some CW/SSB QSOs, but only 3 worked on phone during the afternoon; FT8 was far more productive.
22-Jun-25: Conditions improved for the second day of the Trophy contest, with 4 worked in CW and 33 in SSB, all within Europe.
23-Jun: Not a particularly exciting day with only 6m propagation present, UN7LZ (MO13) being the best of the bunch at 0832.
24-Jun: A mixed day, with 4m propagation predominantly to the south from late afternoon onwards. An interesting evening opening on 6m, with good steady propagation to Newfoundland from 2013, the path still being open at 2140 when I closed down for the night. A less stable path was also present to the Caribbean, where WP3AV (FK78), HC2FG (FI07), and the highlight TI5CDA (EK70), were worked.
Final Results
In a photo finish and in a terrific battle, Gordon MM0GOR just edged it from Martin GM8IEM by a single square. I can honestly say that both Martin and Gordon appeared to be active almost any time that I was active over the last 4 weeks. A fantastic effort by both, but Gordon MM0GOR just wins by the smallest margin. I believed that Martin operating on 6m and 4m was more likely to end up as the winner, but Gordon operating on CW and SSB on 6m only managed to scrape the win.
Tom GM4FDM ends up in 3rd place. Congratulations Tom. John GM0AZC completes the challenge in 4th place and Gordon MM0GPZ ends up in 5th after a final fortnight surge to mid table respectability.
Well done to all and thanks for your reports.
My thanks to Gordon MM0GOR and Martin GM8IEM for their detailed reports once again copied below.
Final Period Report from Gordon MM0GOR
On holiday in EA5 from 23/06-30/06, so using remote back to home station (high-speed internet at the holiday apartment helped).
24/06 – Mostly some EU with an opening to VE around 20:00z, this was followed by Central and Northern countries of South America around 21:00z with KP4, HC and TI worked
25/06 – A Scandinavia only day with only some new grids worked
26/06-03/07 – Only a few new EU grids worked these days with 7X and CN the only DX worked
04/07 – EU again with a very short 30min opening to NA 12:30-13:00z
05/07 – Some late morning EU worked on CW then 6m band crashed out in the afternoon in time for RSGB VHF FD contest – worked 6x UK stations on SSB/CW then gave up at 19:00z
06/07 – EU again with focused opening to Scandinavia only most of the afternoon – worked UA and UN as farthest DX. Good strong signals on CW & SSB in the evening from OH, SM
No JA at all so far this season.
Station setup:
6m: IC-7300, Expert 1K-FA linear running at 500W FT8, 700W CW/SSB, with 4el LFA yagi at 10m.
6m ODX: CE3SX (Grid FF46 Distance 7333 miles)
Here’s a view of my grids worked:
I hope everyone enjoyed themselves in the GMDX Summer VHF Challenge 2025, thanks to all who made the effort to enter.
My 2025 obsession with 6m is now officially over !
73 Gordon MM0GOR
Final Period Report from Martin GM8IEM
All below are FT8 unless otherwise stated, times UTC.
25-Jun to 3-Jul: Patchy and unstable propagation during this period made catching new squares a struggle.
03-Jul: Pleased to catch HK3W (FJ34) at 1951, which marked a turning point in conditions.
04-Jul: Good North American opening starting at 1140 and continuing until 1400. Several new grids worked, the best being EM45. Unfortunately, I had to go out at 1220, so missed the best part of it – the opening reached as far west as EM03.
05-Jul: Poor conditions during the RSGB 50MHz VHF NFD segment which resulted in only 4 SSB/CW QSOs, all within Scotland.
06-Jul: Conditions were better for the RSGB 70 MHz VHF NFD segment, though my linear was tripping out on CW and SSB and I abandoned thoughts of adding to my score. Spirits were lifted by good propagation to Finland and beyond, starting around 1700 and lasting until past 2100, during which several additional FT8 squares were added to the total on 4m and 6m, the furthest of the evening being UN3M (LO61) on 6m. The Challenge finished for me on a high note!
6m ODX: LU1HLH (11339 km), 4m ODX: 5B4AIF (3807 km).
Station setup:
6m: IC-746, Expert 1K-FA linear running at 500W FT8, 1000W CW/SSB, with 6el yagi at 13m.
4m: IC-7300, Gemini 4 linear running at 160W with 7el yagi at 7m and SP-400 masthead preamplifier.
Summary: An interesting Challenge, with the change in scoring rules encouraging modes other than FT8. CW and SSB QSOs were hard to come by outside the UKSMG and RSGB weekend contests, during which conditions were rather poor. During the Challenge, 6m propagation was characterised by long quiet spells, punctuated by some good openings into Europe, although little was worked in the Balkans. Outside Europe, no stations were worked beyond Kazakhstan (MO13) to the east, the Caribbean area gave disappointing results although South America provided some very fine focussed (small footprint) openings. Only two good openings to eastern North America were caught. 4m propagation was good when MUFs rose above 80MHz, and followed a similar pattern to 6m, although no stations outside Europe and the eastern Mediterranean were worked. Overall verdict: Good fun and certainly a challenge.
The vagaries of 6m and 4m propagation keeps you on your toes!
Martin GM8IEM
Thanks once again to all who entered this year’s challenge and submitted logs.
73 Gordon MM0GPZ